RESUMO
INTRODUCTION: Malignant non-melanoma skin cancers (NMSC) are of two main types: basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). In rare occasions, some of the malignant skin lesions show histopathological characteristics of both BCC and SCC and are known as basosquamous carcinomas (BSC). In some cases of large tumors, extensive reconstructive surgery might be needed to correct the skin defect after the primary excision. PRESENTATION OF CASE: We report a case of a 76-year-old Bulgarian male patient who presented with a neglected giant cutaneous tumor with more than a 15-year history of a growing mass in the right deltoid area. On physical exam an enormous exophytic ulcerated and crusted skin lesion measuring around 11×11cm was found. Wide local excision of the lesion with 10-mm resection margins and partial resection of the underlying deltoid muscle were performed due to signs of infiltration. A full-thickness total skin graft from the left inguinal area was harvested to cover the skin defect. Final histopathological examination showed metatypical carcinoma with mixed characteristics of SCC and BCC - BSC, with infiltration of the fatty tissue, deltoid muscle and clear margins of resection, staged as T4R0. Two and a half years after surgery there are no signs of upper arm motor dysfunction and no evidence of local recurrence and distant metastasis on a follow-up PET/CT. DISCUSSION: Following current National Comprehensive Cancer Network's guidelines for primary treatment of BCC, surgical candidates should undergo standard excision with wider surgical margins, postoperative margin assessment and second intention healing, linear repair, or skin graft. Therapeutic strategy for non-operable cases includes administration of radiotherapy or system therapy in the face of Hedgehog pathway inhibitors and programmed cell death protein 1 inhibitor. They can provide an alternative solution to unresectable or difficult-to-treat locally advanced cases of BSC. CONCLUSION: Similarly to BCC and SCC, the first-line treatment option for BCS is surgical excision, but surgical margins should be wider than those for low-risk BCC due to the infiltrative growth pattern of this tumor. Favorable esthetic outcome requires precise planning of the reconstructive technique.